I had a plague of rot after a very rainy summer that I'm still fighting. I used physan (cleans greenhouse algae) directly sprayed on plants (I mix physan and fertilizer together when I water heavy every other week) and some peroxide root soaks before repotting which has helped keep the rot at bay.
I started this on DG when I realized that orchids will come and go and got past blaming myself for deaths(or feeling too cocky about my successes!). I have lots of pics of orchids no longer with me. It's nice to remember that they were once alive and happy here. And maybe I'll try another time with them. After all I understand them a bit more every year.